"King Cotton" is a slogan that summarized the strategy used before the American Civil War (of 1861–1865) by secessionists in the southern states (the future Confederate States of America) to claim the feasibility of secession and to prove there was no need to fear a war with the northern states. The theory held that control over cotton exports would make a proposed independent Confederacy economically prosperous, would ruin the textile industry of New England, and—most importantly—would force the United Kingdom and perhaps France to support the Confederacy militarily because their industrial economies depended on Southern cotton.
By 1861, many of the most powerful governments, now including the North of the United States, had made commitments against slavery, and for this reason, the Confederacy realised that they had to use cotton as the "selling point" of their new republic and not slavery.[1]
From an economical standpoint, the emancipation in the West Indies and the general abolishment of slavery was a failure for Britain, and this was one of the reasons why southerners believed that they were susceptible to changing their minds regarding anti-slavery policies, and thus intervention on their behalf.[2]
The slogan, widely believed throughout the South, helped in mobilizing support for secession: by February 1861, the seven states whose economies were based on cotton plantations had all seceded and formed the Confederacy. Meanwhile, the other eight slave states, with little or no cotton production, remained in the Union.
To demonstrate the alleged power of King Cotton, Southern cotton merchants spontaneously refused to ship out their cotton in early 1861; it was not a government decision. This did not just include holding back the exportation of cotton, but the burning of cotton too, authorised by the Confederate Congress in 1862, in circumstances where there was a danger of the Union gaining Southern territory and taking the cotton.[3] By summer 1861, the Union Navy blockaded every major Confederate port and shut down over 95% of exports. However, the British were able to acquire cotton from alternative locations such as India, Egypt and Brazil. Britain had already abolished slavery, and the public would not have tolerated the government militarily supporting a sovereignty upholding the ideals of slavery.[4]
Consequently, it proved a failure for the Confederacy, as the strategy did not succeed in making the new Confederate polity economically prosperous. The blockade prevented the earning of desperately needed gold. Most importantly, the false belief led to unrealistic assumptions that the war would be won through European intervention if only the Confederacy held out long enough.[5]